Although it is desirable, in angiographic examination of human vascular portions injected with a contrast medium, to scan with an X-ray beam rotating around the patient so as to produce a series of X-ray images at successive angles, a remaining problem is that available rotational X-ray scanners do not rotate fast enough to complete a substantial angular scan, e.g. up to 180 degrees, during the short period while the contrast medium remains in the vascular body portion under examination, e.g. 3 seconds. Extending the time and the amount of injected contrast medium increases the risk to the patient from the medium's toxicity. Available X-ray systems suitable for angiographic examination are limited to accelleration within 360 degrees.
Accordingly it is the object of the present invention to provide an apparatus and method which will make possible an angiographic scan of a human vascular portion though a wide angle during the short period that an acceptably safe injection of contrast medium remains in the portion.